Dictionary > Autophagy

Autophagy

Definition
noun
A programmed cell death characterized by biochemical events leading to self-digestion through the destructive action of enzymes produced by the cell itself, often as a defensive or self-preservation response
Supplement
The death of a cell may be physiological (i.e. programmed cell death) or non-physiological (i.e. necrosis). In the former, it is described as physiological because the death of the cell is mediated by an intracellular program.1 The programmed type of cell death is further categorized into type I cell death (or apoptosis) and type II cell death (or autophagy).
Autophagy is the process involving biochemical events catalyzed by enzymes produced within the cell that leads to self-digestion. The organelles and misfolded proteins become contained inside a vesicle (referred to as autophagosome). They are then directed into the lysosomes for degradation. Thus, autophagy is a means of the cell to maintain intracellular homeostasis. Not all autophagy ends in cell death. In this case, the cell may still survive. Nevertheless, there are also instances wherein autophagy leads to cell death, such as in the case of a cell that has become cancerous and evaded apoptosis.
Also called:

  • type II cell death
  • auto-cannibalism
  • autophagocytosis

Compare:

See also:

Reference(s):

1 Engelberg-Kulka H, Amitai S, Kolodkin-Gal I, Hazan R (2006). “Bacterial Programmed Cell Death and Multicellular Behavior in Bacteria”. PLoS Genetics 2 (10): e135.


You will also like...

Pollution in Freshwater Ecosystems
Pollution in Freshwater Ecosystems

There are many environmental factors that arise due to the usage of water in one way or another and for every action tha..

Endemic Flora of New Zealand
New Zealand’s Unique Flora

If New Zealand has lots of unique animals, it's also got a whole lot of unique plants. Find out more about some of them,..

Evolution of Life - Ancient Earth
Evolution of Life – Ancient Earth

Autotrophs flourished, absorbing carbon and light. Soon after, primitive life forms that could assimilate oxygen thrived..

Darwin's Finches - Natural Selection
Darwin and Natural Selection

This tutorial investigates the genetic diversity in more detail. It also delineates how certain alleles are favored over..

Birth of a Human Baby
Birth of a Human Baby

Following nine months inside the mother's womb is the birth of the baby. Know the different stages of the birthing proce..

"Cronopio dentiacutus", a prehistoric mammal (an illustration)
Mammalian Ancestors

Mammals are a diverse group of organisms, where most of them develop their offspring within the uterus of the mother. Ov..

Related Articles...

No related articles found

See all Related Topics